Who among the following has NOT been the Chief Justice of India?

Of the four names, three have headed the Indian judiciary as Chief Justice of India: K. G. Balakrishnan (37th, 2007 to 2010), S. H. Kapadia (38th, 2010 to 2012) and Altamas Kabir (39th, 2012 to 2013). N. Gopalaswami, however, belonged to the executive: he was an IAS officer who served as the 15th Chief Election Commissioner of India (2006 to 2009) and never held the office of Chief Justice of India. Hence N. Gopalaswami is the person who has NOT been the Chief Justice of India.